We conduct integrative and comparative research broadly focused on identifying the physiological and behavioral mechanisms that underlie adaptive divergence in populations and species. Two common threads of our studies include thermal physiology and the implications of diet evolution. Most of our research is conducted on amphibians and reptiles, particularly desert-dwelling species from the southwestern United States and Argentina. Current student and lab projects include (1) quantifying the temperature-dependent performance of atypical geckos (diurnal and cold-climate species); (2) testing the cold-hardiness strategies of high-elevation frogs and liolaemid lizards from the Andes of Argentina; (3) characterizing physiological, morphological, and genomic changes associated with climatically driven selection on the widely introduced Mediterranean House Gecko (Hemidactylus turcicus); (4) identifying the costs and benefits of maternal care in Phymaturus lizards; (5) testing the physiological mechanisms underlying ecological speciation in the Western Skink complex (Plestiodon skiltonianus); and (6) characterizing microbial communities and host–endosymbiont relationships among species of herbivorous lizards and their gut bacteria.